No. 16. — Moniloporidae , a new family of Palaeozoic Corals. 
By Amadeus W. Grabau. 
The genus Monilopora was erected by Nicholson and Etheridge 
in 1879 for Cladochonus crassus M’Coy. This species differs 
from the typical species of Cladochonus in the open character of 
the visceral chambers of the corallites, and especially in the struc¬ 
ture of the wall, which consists of concentrically added layers of 
sclerenchyma, with an open reticulate structure appearing in some 
parts. 
The described species are Monilopora crassa (M’Coy) N. and 
E. from the Carbonic limestone of Great Britain and Ireland and 
31. antiqua Whiteaves from the middle Devonian of Canada. To 
these I add 31. beecheri from the lower Carbonian of Indiana. 
Closely related to Monilopora is the new genus Ceratopora. 
This is represented by three species, C. jacksoni , sp. nov., C. dis- 
torta , sp. nov., and C. dichotoma , sp. nov., from the Hamilton shales 
and limestones of western New York and the Falls of the Ohio. 
Monilopora and Ceratopora, each represented by several species, form 
a natural association, and the features which they have in common 
separate them from other Palaeozoic corals. Ceratopora appears 
earlier than Monilopora and is less specialized in structure. For 
these two genera the family Moniloporidae is proposed. 
Moniloporidae, fam. nov. 
Compound, branching coralla, composed of cylindrical or funnel- 
shaped corallites, which either remain connected by their visceral 
cavities, or become separated within by the disposition of continu¬ 
ous layers of sclerenchyma. Tabulae absent. Walls thickened by 
the addition, internally, of concentric layers of sclerenchyma which 
either are closely applied or leave variously shaped cavities or lacu¬ 
nae between successive layers. Septa absent, or represented by 
costae and by trabeculae. Asexual reproduction by basal and lat¬ 
eral gemmation. Range from Devonic to Carbonic. 
